1. Field of the Invention
The present invention relates to an information processing device in which a synapse strength matrix (Tij) representing inter-neuron wiring in neural information processing can be written by rays of light from light-emitting elements formed in the device.
2. Prior Art
FIG. 1 is a diagram showing an integrated circuit in an information processing device simulating a neural circuit network which is shown, for example, on page 625 of "Science", 233, by J. J. Hopfield et al (1986). In the drawing, the reference numeral 1 indicates a unit of neurons each of which includes a resistor 2, a capacitor 3 and an amplifier 4. The reference numeral 5 indicates a Tij indicative of a level of interaction between neurons. The reference numerals 6 and 7 respectively, indicate an input line connected to the neuron 1 and an output line extending therefrom.
The operation of this integrated circuit will now be described. Information carried by an external signal is supplied, as an input to the processing device, to the neuron 1 in the form, for example, of electric current, through the input line 6. The input line 6 crosses the output line 7 of another neuron at the Tij portions 5 before the input line 6 reaches the neuron 1, the current input to the neuron 1 is affected by the output line 7. The Tij portions 5 generally consist of a fixed resistor formed within the information processing device when that device is manufactured. In the neuron 1, the resistor 2 and the capacitor 3 convert the input current value to a voltage value, which is amplified by the amplifier 4, whereby an output of firing (+V) or suppression (-V) is emitted. When the respective outputs of the neurons of the entire network have attained stability, optimum target information is obtained among these output values.
A conventional information processing device being constructed such as described above, neurons, wiring lines and Tij portions have to be previously formed in the device. As a result, the number of neurons that can be integrated in the device is limited. In addition, the value of Tij portions cannot be changed.